What is "high res"?

Al83

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My high street processor burned a cd on my request. Files under the "high res" folder are typically 800kb in size. Is this typical of a high street processor? The images don't look great on my computer screen....:(
 
800kb sounds quite small. Have a look at Ilford's scanning service here. Medium scans from 35mm are 2048x3072 pixels = 18Mb, large scans are 4492x6774 pixels = 87.1Mb - that's more like "high res" to me.
 
Very low res. File size is a crude way to gauging scan quality, as its a product of the scanned resolution (no. of pixels), the level of compression used, and the file format. 800kb is very low res though, and low enough to say you're looking at a low res, highly compressed jpeg. High res scans should be high in resolution and low in compression. Tiff format scans are always nice, but jpegs are more than acceptable.

A good yardstick can be to think of the resolution you would need to print, with higher quality prints generally acknowledged to benefit from 300- 360 pixels per inch, with decent prints to be had from 180- 240 pixels per inch. This should give you an idea what your scans will be best suited for.

In all, resolution = how big you can print, compression level = how much leeway you will have in editing the files, likewise with file format, tiffs giving you greater editing freedom, jpegs less editing freedom.
 
Fifteen to twenty years ago, when consumer labs started buying scanners, anything upward of VGA (0.3MP) was high res. A decade ago, when most of them ceased to upgrade their film handling (processing and scanning) hardware, 1MP was still considered high res.
 
Minilabs put on the CD typically two folders; one for the thumbnails that make the index card and one that is scanned at the size used to make the prints.
My guess is the 800kb files are 4x6 at 315ppi (assuming you have had them scanned on a Fuji Frontier).
The 'high res' label is just a file name for the print size scans, so when you go back to the Fuji kiosk for re-prints the software looks for the thumbs (low res) folder for screen display and then will print from the 'high res folder' they are given those names for the automatic machines benefit.

If you want actual high res scans from a minilab you need to ask the operator to scan only at around 8x12" or larger, this slows down the machine to about 30 seconds per scan-so ask them to do them at the end of the day.
The 4x6 scans take 2-3 seconds, this is the default size for most minilabs and results in a file size typically less than 1mb.
 
My high street processor burned a cd on my request. Files under the "high res" folder are typically 800kb in size. Is this typical of a high street processor? The images don't look great on my computer screen....:(

What is meant by "high res" is relative; relative to the desired reproduction size. In my book, "high res" is 300ppi at intended print or display size. Since the most common photo "enlargement" size is roughly 8x10 (7x10, 8x12), I wouldn't consider anything less than about 2400x3600 pixels to be high res.

Where I work (a photographer's gallery), "high res" generally means TIFF files in the 100mb to 1gb range. Our most common print sizes are in the 29x44" to 40x60" range. The master files sometimes exceed PSD's max file size and have to be stored as PDB files. "Medium" sized files, for us, are 20x30in 300ppi files. Most of what I work with are larger.
 
Is this typical of a high street processor? The images don't look great on my computer screen....:(

No matter what the size of the file, I have never really gotten a scan that was great from the supposed pro labs out there or from the few consumer scanners I've tried. Tells you what the industry is thinking about film when they aren't making great scanners for consumers. Sad.
 
I have made some wonderful scans on both my Fuji frontier and even better ones on the Agfa D lab.
The skill is with the operator, good operators with pro level software can give surprisingly good results, I'd go as far as saying for output less than 10x15 the limitation isn't the scanner.
Here's a scan I did on the Agfa D lab
70960954.jpg


No customer of mine ever left the prolab unhappy, if they did it's because they didn't let us know.
 
No matter what the size of the file, I have never really gotten a scan that was great from the supposed pro labs out there or from the few consumer scanners I've tried. Tells you what the industry is thinking about film when they aren't making great scanners for consumers. Sad.

Really? I get great scans from my Nikons, and most of the Plustek users I know are happy with their results.
 
When I get C-41 processed by my local lab (KSP in Palo Alto, CA), I ask for a CD so I can decide which ones I want to scan myself on my Coolscan 9000. They're about 350-450K each on the CD, which is plenty big enough to see if I like the image well enough to do a better scan. By that standard, 800K would be a "higher res" option, but not very high res. When I scan them as 48-bit TIFFs, I get ~65Mb files. When I shrink them to 1000x1500 pixels and save as jpeg's for Flickr etc., I still end up with a ~700-800K file.
 
Hi,

Quoting 800kb tells us very little, we need to know the size in megapixels. Then we'll probably tell you that it's high compression as a jpg file.

Having said that it's still pretty meaningless as the subject matter can or can't often take high compression.

As I see it these scans are for cataloguing on the computer and not for printing. The negatives are for printing, either by scanning or an enlarger.

BTW, "high resolution" changes every time a new camera appears. At one time it was 1280 x 1024 for a pro dSLR...

Regards, David
 
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